after PSU failed and repalced, XP loop boots

Hey, the other morning i turned on my computer and nothing happened, turned out to be a defective PSU... so i changed that, and now it has power, And when the grub bootloader comes up ( Dual boot of gentoo and XP), i choose XP, and it starts loading for about 4 seconds and then when the blue bars start going across under the logo, it reboots itself and goes to grub again. But when i choose gentoo, it works fine. This has never happened before the PSU went bad. Does anyone know what the problem could be? I dont think its my RAM, because i go to system monitor in gnome and it says user memory: 111.2 mbs of 1003.1 mib. But im not really sure.
Any one have any ideas?
Thanks
Andrew

yess sorry i meant to mention that..
i cannot boot itno
Safe mode
Safe mode with networking
safe mode with command prompt
last known good configuratoin
Start widnows normally
All do the same loop boot thing

I run repair from the windows XP professional setup screen and i get:
Setup did not find any hard disk drives installed in your computer.
Make sure any hard disk drives are powered on and properly connected to your computer, and that any disk-related hardware configuartion is correct. This may involve running a manufacterer-supplied diagnostic or setup program.
setup cannot continue. :S... i did take my harddrive out and put it into someone elses computer to get some files off of it that i needed... But i never changed the jumpers.. and my linux boots fine off the same hard drive :S

hm thanks i didnt see that post.. I can't do that because the first step is to boot form the windows CD, and hit R to get into the recovery console. However when i hit R to do that, ^^ the above post is the output:S.... very weird seeing as i doubt my HD is in wrong if my gentoo boots...

hm thanks i didnt see that post.. I can't do that because the first step is to boot form the windows CD, and hit R to get into the recovery console. However when i hit R to do that, ^^ the above post is the output:S.... very weird seeing as i doubt my HD is in wrong if my gentoo boots...

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